What is Cloud Computing?

Cloud computing is the delivery of virtualized IT resources over the Internet. It’s computing as a service, delivered on an on-demand, pay-per-use basis, through a cloud services platform.

Cloud computing definition

“The cloud” isn’t a place, but a method of managing IT resources that replaces local machines and private data centers with virtual infrastructure. In this model, users access virtual compute, network, and storage resources made available online by a remote provider. These resources can be provisioned instantly, which is particularly useful for companies that need to scale their infrastructure up or down quickly in response to fluctuating demand.

Benefits of cloud computing

While cloud computing may not be right for every application, for many businesses, moving some or all IT operations to the cloud can have big advantages over managing them in-house, namely:

Low up-front investment: With cloud computing, a major portion of the IT budget becomes an operating expense rather than an upfront capital expenditure. Businesses no longer need to set up expensive data centers before opening their doors or embarking on new initiatives.

Cost efficiency: Whether you’re a small business or a large enterprise, you can reap the same benefits from the massive economies of scale achieved by cloud service providers. CSPs are able to maximize the amount of fully utilized hardware they’re running, conserving energy and other costs---savings they’re ultimately able to pass on to their customers.

Highly elastic capacity: Cloud computing resources are not only highly scalable, i.e. easy to expand, but highly elastic, meaning that capacity and costs can also be ramped down during periods of light demand.

Ease of use and maintenance: With cloud computing, resources and updates can be deployed in an automated, standardized fashion, increasing accessibility and eliminating inconsistencies and the need for manual updates. There’s also no need for your team to physically maintain servers or data center facilities.

Easier innovation: Both within the IT team and across businesses at large, cloud computing often paves a smoother path of innovation. Freed from the operational burdens of “racking and stacking,” IT departments have the bandwidth to drive business process improvements that can have far-reaching effects. Meanwhile, their business counterparts are able to quickly and cheaply resource experimental programs and then build them up or scale them down without the burden of detailed infrastructure planning or upfront, long-term investment.

Better business continuity: Because of the virtualized nature of cloud computing infrastructure, creating backup copies of data and operating systems and initiating failover procedures can be automated. This allows for much better data protection and availability than most on-premises systems can provide.

Types of cloud computing services

While cloud computing has many advantages, enterprises may have some concerns, including:

Infrastructure as a Service (IaaS): The most basic form of cloud computing, IaaS gives users access to infrastructure basics such as server space, data storage, and networking, which can be provisioned via an API. This model comes the closest to replicating the functionality of a traditional data center in a hosted environment.

Platform as a Service (PaaS): This model offers a full-fledged development environment, eliminating the need for developers to deal directly with the infrastructure layer when deploying or updating applications.

Software as a Service (SaaS): SaaS applications are designed for end users, with all infrastructure provisioning and development happening behind the scenes. From business applications such as word processing and spreadsheet programs, to CRMs, photo-editing suites, and video-hosting platforms, SaaS apps provide a huge range of functionality in the cloud.

Cloud deployment models

There are three basic cloud computing models available to businesses:

Public cloud: Public cloud is shared cloud infrastructure that is owned, maintained and managed by a cloud provider like Amazon Web Services or Microsoft Azure. The chief benefits of public cloud are its on-demand scalability and pay-as-you-go pricing.

Private cloud: This type of cloud runs behind a firewall on an enterprise’s intranet and is hosted in a data center dedicated to that organization. Private cloud infrastructure can be configured and managed according to an individual company’s needs.

Hybrid cloud: As the name suggests, the hybrid cloud model allows companies to leverage both public and private cloud solutions. With hybrid cloud, organizations can take advantage of the strengths of each cloud model to enable flexibility and scalability while protecting sensitive data and operations.

Cloud security

Security is one of the primary concerns of companies looking to move part or all of their IT operations to the cloud. In some industries, data security compliance regulations dictate that some applications remain in private data centers, necessitating private or hybrid cloud models. However, there are several security advantages to cloud computing, including:

State of the art technology: Public cloud is free from the security risks inherent in most on-premises data centers, which often mix legacy systems with newer technologies. Cloud providers are able to implement state-of-the-art encryption and other security measures system-wide, and perform maintenance in an automated fashion.

Dedicated staff: Cloud providers’ reputations and businesses depend on keeping customer data secure. They have staff specifically dedicated to security monitoring and maintenance, which may mean they’re able to do a better job of it than an individual company’s IT department, which typically handles a wide range of tasks.

High availability: Redundancies are built into cloud computing, so that even if some servers fail, your online applications will continue to run without interruption. 24/7 monitoring and uptime guarantees are a standard part of cloud computing vendor contracts.

Better data protection and disaster recovery: Cloud-based backup solutions tend to be relatively inexpensive and easy to use. The cloud computing model also means key files aren’t trapped on individual machines, which can be easily tampered with, and will inevitably fail at some point.

Key cloud computing terminology

Here are a few important cloud computing phrases you’ll want to understand:

Cloud application: A web-based software program, or “hosted application,” such as those offered by SaaS vendors.

Cloud broker: An intermediary that has access to several cloud service providers and can provide individual clients with the best cloud services to suit their particular needs. In a hybrid IT environment, IT departments often become cloud brokers.

Cloud management platform: In a business where operations are spread between two or more clouds and/or on-prem infrastructure, a seamless cloud management experience is critical when it comes to making everything work together in a way that maximizes efficiencies and optimizes costs. Cloud management tools can help bring everything together on a unified dashboard.

Cloud migration: The act of moving data and applications from private machines or data centers into the cloud.

Cloud native: Applications developed specifically for cloud-based usage. These applications are typically built as microservices in containers, using open-source code, to fully take advantage of the inherent flexibility and scalability of cloud computing.

Container: Containers enable the virtualization of software applications by providing lightweight runtime environments that include everything apps need in order to run, making them highly portable. This is foundational to “cloud native” computing.

Hypervisor: Also called a “virtual machine monitor” or “VMM,” a hypervisor can be software, hardware, or firmware, and is the layer that allows for the virtualization of the resources offered by physical infrastructure. In other words, hypervisors are management systems that allow many guest virtual machines (VMs) to make use of the same resources.

Measured service: A key component of cloud computing, “measured services” means that cloud service providers monitor and meter resource usage of various resources and bill accordingly.

Middleware: The software management layer that sits between an application and a network and makes it possible for networked devices to communicate. In cloud computing, middleware is often used to support complex distributed systems.

Microservices architecture: Small, modular programs that are linked together to build complex applications. Because they’re self-contained, microservices can be individually deployed and updated, enabling agile development.

Multi-cloud: Businesses frequently make use of more than one cloud service provider. For example, ta business may use an IaaS or PaaS provider for their own systems and internal or customer-facing applications, while also using one or more SaaS applications from other providers to complete aspects of their work.

Multi-tenancy: Public cloud providers pool compute resources that are shared by multiple consumers. Resources are dynamically assigned according to demand.

Software-defined infrastructure: Software-defined infrastructure can be fully deployed and controlled by an application, with no human involvement. This enables applications to specify and configure the hardware they need to run on as part of their code. Software-defined infrastructure is a fundamental building block of all cloud technology.

Virtual machine: Composed of hardware and software, a virtual machine is software-defined operating system or application environment that contains all the same components as, and runs like, a physical computer.

Workload: A discrete computing task that takes place within the context of running an application. In cloud computing, application workloads may be distributed across different systems.